Until a black swan was sighted in Western Australia by European explorers, it was assumed that swans were white. It was part of the definition of swans that they were white. But you only need one variation to show up your wrong assumptions.

Financial trader-turned writer Nassim Taleb popularized the idea of the ‘Black Swan’ event. They: happen against all expectations; have an extreme impact; and are afterwards explained away as if they were predictable.

No one foresaw the severity of World War One, the rise of Hitler, the sudden collapse of the Soviet bloc, the spread of the Internet, or 9/11. Neither does anyone foresee the particular ideas, fashions, or art genres that suddenly come into vogue.

“A small number of Black Swans explain almost everything in our world, from the success of ideas and religions, to the dynamics of historical events, to elements of our own personal lives.”

The effect of Black Swans is increasing because the world is more complicated, yet at the same time the combination of low predictability and large impact causes a problem for the human mind. We are built to focus on the known and visible.

Taleb imagines two places to express our ways of seeing the world. ‘Mediocristan’ is a state in which there is an equal relation between effort and result, where the future can be predicted, and where most things fall into a wide band of averages.

‘Extremistan’ is an inherently unstable, unpredictable, winner-takes-all, kind of place. It is the latter that we actually live in, and accepting the fact is the first step to thriving in it.

As a ‘sceptical empiricist’, Taleb’s philosophical heroes are David Hume, Sextus Empiricus, and Karl Popper. He is very critical of academic philosophy. While interesting, it has nothing to do with the real world - a world in which people have to live with uncertainty.

Black Swans make a mockery of attempts to curb uncertainty. In your life, how many things, from meeting your spouse to the profession you entered, came according to plan or on schedule? Who expected that you would be fired, exiled, enriched or impoverished?

“Black Swan logic makes what you don’t know far more relevant than what you do know”, Taleb says, because it is these big unexpected things that shape our lives.